1. Field of the Invention
The present invention relates to an automatic hydraulic valve and, more particularly to an automatic, sequentially-controlled, metering, multiple valve having a fluid inlet and a plurality of fluid outlets, and being operative to selectively connect the inlet to any of the outlets in any varying sequence for any amount of time.
2. Description of the Prior Art
As is well known in the art, various problems and difficulties have been and are still being encountered in providing suitable means for regulating the timing and volume of water that is required to properly irrigate large parcels of land -- particularly where numerous sections are involved and where the surface area to be watered is of considerable magnitude.
Various types of control valves in conjunction with sprinkler systems are used for the flow of large volumes of water. However, these devices have features that restrict their use, and are complicated to operate and expensive to maintain.
Additionally, many uses presently exist for hydraulic timing valves of the type which are operative, upon activation, to provide a predetermined amount of water flow from the inlet to the outlet thereof and which automatically shut off thereafter. Some of the most common uses of such valves are as flushing valves for use in connection with lavatories and similar types of sanitary apparatus, as automatic faucets, and as shut-off valves for industrial and commercial uses.
Valves of this type generally include a timing member positioned within a valve body which is operative to automatically close the valve after the flow of a predetermined amount of water therethrough. One such timing valve is disclosed in U.S. Pat. No. 3,543,795 issued Dec. 1, 1970, for Hydraulic Timer Valve and Actuator Therefor. That timing valve includes a generally cylindrical and hollow housing and a valve member which is operative to reciprocate between a valve seat in one end of the housing and a timing chamber in the other end to control the flow of fluid from the inlet to the outlet of the valve. Small droplets of water are metered from the valve inlet through an orifice in the valve member, at a fixed rate, into the timing chamber, thereby exerting pressure on the valve member to continually push it into seating relationship with the valve seat to thereby close the valve. Such valve also includes an adjustable cap for determining the time setting thereof.
The above patent points out that many situations exist where it is desirable or necessary to be able to vary and accurately control the time setting of the valve. For example, if such a valve were to be used in connection with an automatic sprinkler system, it would be desirable if the time setting of the valve could be adjusted depending upon soil conditions so that a proper amount of water could be provided thereto. In such a situation, the ability to vary the time setting of the valve over a wide range would be a highly useful feature. It is also pointed out that, in many commercial and industrial uses, a high degree of accuracy and repeatability are important.
To solve this particular problem of the prior art, this patent discloses a mechanism whereby the relatively simple expedient of rotating a valve cap may be utilized to vary the time setting of the valve accurately, within the range of a few minutes to an hour or more. This feature is combined with a unique metering technique which permits the time setting of the valve to be extremely accurate, with a high degree of repeatability in valve operation.
Finally, the above patent also points out that for many uses, such as in connection with automatic sprinkler systems, it is desirable to be able to control the activation of a second timer valve automatically in response to the shutting off of a first valve. For example, in a situation where several parcels of land are to be watered and the water pressure is only sufficient to water one parcel at a time, it would be desirable if the hydraulic timer valve for each parcel could be operated automatically in response to a prior timer valve shutting off. In order to solve this problem, the patent provides an automatic valve actuator which monitors the operation of a first automatic timer valve to determine when the valve shuts off and which turns on a second valve which will then operate in the same manner as the first valve.
While the hydraulic timer valve and the actuator therefor of this U.S. Patent have been found to have distinct advantages over the prior art in solving the problems discussed previously, still other problems exist. More specifically, because of the construction of the automatic valve actuator, all hydraulic timing valves are identical and each includes the entire timing mechanism and metering apparatus. This duplication of timing mechanisms and metering apparatus in every valve has been found to represent an unnecessary expense. In addition, a difficulty has been encountered in controlling the sequence of operation using the automatic valve actuator. More specifically, the operation of that valve actuator requires each valve to operate in sequence; and it is not possible to selectively skip individual valves once a sequence is established.